Pharmacokinetic-pharmacodynamic relationship of levodopa with and without tolcapone in patients with Parkinson's disease.

Objective: To investigate the effect of administration of the catechol-Omethyltransferase (COMT) inhibitor tolcapone on the concentration-effect relationship of levodopa in patients with advanced Parkinson's disease and on-off fluctuations.

Design: Nonblind single-group 2-period pharmacokinetic-pharmacodynamic study.

Patients And Participants: 12 patients, mean age 59 years, with idiopathic Parkinson's disease and response fluctuations.

Bilateral hyperalgesia to chemical stimulation of the nasal mucosa following unilateral inflammation.

The aim of the present study was to investigate the bilateral sensory changes to chemical noxious stimuli in the trigeminally innervated areas following unilateral nasal inflammation. Twenty healthy volunteers took part in five experiments. Intranasal inflammation was induced by means of a constant flow of cold air (145 ml/s); temperature and humidity of the airstream were varied across experiments.